You need to concede a lot of the fighting going on in Africa too.
As for Imperial Japan, the emperor worship was far more than a sales technique. The leadership were true believers. The god status of their emperor, their head of state, made all other heads of state vastly inferior, all other peoples vastly inferior, the wishes of all others vastly inferior. Imperial Japan's "superiority" was firmly based in their religion, it inspired their "divine destiny" to rule vast parts of Asia.
As for Naziism, it manifested religious overtones and included efforts to create an alternative religious experience for the people that predated the start of the war. Early on they absolutely recognized the power of religion and were creating an alternative one to displace christianity. It was far more than a simple method of selling the war. Its religious-like tenets, mythologies, religious knights were also part of their belief in their "superiority", in their "destiny" to rule Europe. It really was a "religion", not an established one, an emerging one and thankfully a failed one.
And now that you inspired further thought we have the communist states of Stalin's Soviet Union and Mao's Communist China. Here too we have a religious-like activity, a worship of the state. Again, not a sales method but a fervent belief system. I suppose you could counter with all sort of euphemisms regarding Stalin's and Mao's states but at its heart we will also find a worship of the state, a faith based belief system, numerous religious-like behaviors. The newness of such belief systems don't really undermine their religious-like nature.
In short you seem to be focused on established religions providing inspiration. I'm focused on a "religious" belief system being behind the motivations for conflict. I think the former is a more valid basis for examining the influence of religion on conflict.